This beautiful chart is French. The Guide de la Santé par les Vitamines des Aliments by monsieur A. Orain, the book which is praised as a guide for correct use on the backside, had a second edition in 1946 (thank you Google). This is the only indication I have about the age of this poster.

I like almost everything about it: the use of colour is vibrant. The size comes as a surprise: a 13 by 20 cm leaflet folds out to 74 by 55 cm poster, the title flaps showing only in the end. Apart from the rather clumsy cover title, the type is great but a bit of a mix: a very linear egyptian and its narrow version plus a clarendon type for the big titles, Futura Oblique and Metro for the text. For subtitles a wide grotesque and a script that comes close to Berthold Ariston are used. Inside the graphs the lettering seems executed by hand, reminiscent of technical drawing.